package beanstao.util;

import java.security.MessageDigest;

public class MD5
{
	public static String getMD5(String s)
	{
		char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
		try
		{
			byte[] strBytes = s.getBytes();
			// 使用MD5创建MessageDigest对象
			MessageDigest md5 = MessageDigest.getInstance("MD5");
			md5.update(strBytes);
			byte[] md = md5.digest();
			int j = md.length;
			char str[] = new char[j * 2];
			int k = 0;
			for (int i = 0; i < j; i++)
			{
				byte b = md[i];
				// 将每个数(int)b进行双字节加密
				str[k++] = hexDigits[b >> 4 & 0xf];
				str[k++] = hexDigits[b & 0xf];
			}
			return new String(str);
		}
		catch (Exception e)
		{
			return null;
		}
	}

	// 测试
	public static void main(String[] args)
	{
		System.out.println("“中华人民共和国”的MD5加密后：\n" + MD5.getMD5("中华人民共和国"));
		System.out.println("http://www.baidu.com/的MD5加密后：\n" + MD5.getMD5("http://www.baidu.com/"));
	}
}
